Enhancements in video imaging, data storage capabilities, and satellite location technology have lead to the relatively widespread use of georeferenced video in numerous applications such as recognizance, surveillance, surveying, and the like. Generally speaking, georeferenced video includes video imagery frames encapsulated in a transport stream along with geospatial metadata that correlates the pixel space of the imagery to geospatial coordinate values (e.g., latitude/longitude coordinates).
Given the large amounts of georeferenced video data that can be generated and stored with technology, it can become difficult to communicate the video and associated metadata to users in a relatively straightforward and intuitive way. Various approaches are used to communicate video-related information to users. One approach is set forth in U.S. Pat. No. 7,559,017 to Datar et al., which discloses a system for transferring annotations associated with a media file. An annotation associated with a media file is indexed to a first instance of that media file. By comparing features of the two instances, a mapping is created between the first instance of the media file and a second instance of the media file. The annotation can be indexed to the second instance using the mapping between the first and second instances. The annotation can be processed (displayed, stored, or modified) based on the index to the second instance.
Another potential difficulty with georeferenced video is how to provide desired situational awareness. Various approaches for improving situational awareness have been developed. One example is set forth in U.S. Pat. No. 6,392,661, which discloses an apparatus for arranging and presenting situational awareness information on a computer display screen using maps and/or other situational awareness information, so that greater amounts of relevant information can be presented to a user within the confines of the viewable area on small computer screen displays. The map display layout for a screen display utilizes multiple, independent map displays arranged on a computer screen to maximize situational awareness information and display that information efficiently. The apparatus provides the ability to independently scale with respect to distance, time and velocity, as well as zoom and pan each map on the screen display.
Another problem which may be encountered with sensor data providing georeferenced video is that position accuracy may vary from one sensor type to the next. One approach for addressing inaccurate geospatial images through the use of image registration, i.e., where newly captured images are compared with reference images with known accurate coordinates to provide a basis for correcting the newly captured image geospatial metadata. In accordance with one exemplary approach, U.S. Pat. No. 6,597,818 to Kumar et al. discloses a system for accurately mapping between image coordinates and geo-coordinates, called geo-spatial registration. The system utilizes the imagery and terrain information contained in a geo-spatial database to align geodetically calibrated reference imagery with an input image, e.g., dynamically generated video images, and thus achieve a high accuracy identification of locations within the scene. When a sensor, such as a video camera, images a scene contained in the geo-spatial database, the system recalls a reference image pertaining to the imaged scene. This reference image is aligned with the sensor's images using a parametric transformation. Thereafter, other information that is associated with the reference image can be overlaid upon or otherwise associated with the sensor imagery.
Tracking objects within georeferenced video feeds is also a desirable feature that may be problematic in some circumstances. One particularly advantageous system in this regard is the Full-Motion Video Asset Management Engine (FAME™) from the present Assignee Harris Corporation. The FAME™ system speeds the process of analyzing a wide range of intelligence information. For geospatial analysis, the FAME™ system has a mapping interface that provides a visual display for the sensor track and location of frames of video from an unmanned aerial vehicle (UAV) or other source. This tool allows indexing, search, retrieval, and sensor tracking in real time during play out. Further exploitation of geospatial metadata is done by extracting embedded Key-Length-Value (KLV) metadata from the video stream.
Despite the advantages of such approaches, further functionality may be desirable for processing and displaying georeferenced video feeds.